The present invention relates to improvements to couplings for coupling the thills or shafts of a racing sulky to the harness saddle.
The thills or shafts of racing sulkies are typically attached to the harness saddle by various strap arrangements which, when secured, bind the shaft to the saddle in a position in which the shaft is quite firmly restrained against movement in any direction relative to the saddle. Because the saddle in turn is firmly cinched to the horse, the saddle moves with that portion of the horse's body to which it is cinched and thus twists and moves up and down and from side to side as the horse strides or leans to one side when going around a turn. Because of the relatively rigid interconnection between the saddle and the sulky shafts, movements of the type referred to above are resisted by the shafts, thus absorbing a certain amount of unproductive energy from the horse.
The rigid coupling between the sulky shafts and saddle is considered generally desirable in order to assure the sulky will closely and precisely track the horse and will not swing wide of the horse in turns or when maneuvering in close quarters.
The present invention is especially directed to a shaft-to-saddle coupling which will enable the sulky to precisely track the horse and yet at the same time will permit, within a limited range, free relative movement of the shaft relative to the saddle to minimize the resistance of the coupling to displacement or twisting motion of the saddle generated by body movement of the horse in striding or in leaning into a turn.